Wash pump control based on predicted wiper arm position using hood mounted spray nozzles

ABSTRACT

A windshield window wiping system, including a wiper blade in contact with a windshield window; a wiper motor operatively connected to the wiper blade, configured to perform a wiper blade stroke; a reservoir for a wash fluid; a first hood mounted nozzle, configured to project the wash fluid toward the windshield window; a wash pump, wherein the wash pump is hydraulically connected to the first hood mounted nozzle; and a first electronic circuit, configured to estimate a position of the wiper blade during the wiper blade stroke based on an input to the first electronic circuit and to synchronize the projection of the wash fluid toward the windshield window with the estimated position of the wiper blade. In other aspects, a method of wiping a windshield window and a non-transitory computer readable medium are provided.

BACKGROUND

Windshield wipers are an important safety feature of modern vehicles andare used to remove rain and vision obstructing dust from the windshieldsof automobiles, trains, ships, and airplanes. In order to effectivelyremove dust from the windshield, a windshield wiper fluid is projectedtoward the windshield to be cleaned. Such windshield wiper fluid maycontain, for example, water, alcohol, detergent, among otherconstituents. The volume ratio of the individual windshield wiper fluidconstituents may be chosen such as to prevent freezing of the vehiclewindshield wiper fluid in the climate of intended vehicle use. Areservoir may hold a sufficient amount of windshield wiper fluid toallow the vehicle to be safely operated for extended periods betweenrefilling the reservoir.

The actual implementation and features of a windshield wiping system ina vehicle are driven by several considerations. One of theseconsiderations is how effectively the windshield wiper fluid is beingused during the wiping of the windshield. For example, projecting thewindshield wiper fluid toward the windshield far in advance of thewindshield wiper action may result in partial or complete runoff of thewindshield wiper fluid from the windshield without being utilized duringthe windshield wiper cleaning action. Further, the distribution of theprojected windshield wiper fluid on the windshield may also play a rolein how effective the windshield wiper fluid is being used. For example,concentrating the projected windshield wiper fluid on a single spot ofthe windshield may lead to local excess of windshield wiper fluid on thewindshield and may result in runoff of only partially utilizedwindshield wiper fluid. However, runoff of unused or underutilizedwindshield wiper fluid should be minimized from an environmentalperspective.

Another consideration is the cost-effectiveness of the windshield wipingsystem in a vehicle and the competitive pricing situation in the overallmarket. On the one hand, although a windshield wiping system may behighly accurate, reliable, and effective, the actual implementation in avehicle on the other hand may be prohibitive from a cost perspective. Asuitable tradeoff may have to be found that allows several of the aboveconsiderations to be simultaneously satisfied to yield an acceptableoutcome. In that respect, it may be beneficial to explore how additionalelements of a windshield wiping system may be advantageously combinedwith vehicle elements to minimize cost.

SUMMARY

In general, in one aspect, one or more embodiments disclosed hereinrelate to a windshield window wiping system, including a wiper blade incontact with a windshield window; a wiper motor operatively connected tothe wiper blade, configured to perform a wiper blade stroke; a reservoirfor a wash fluid; a first hood mounted nozzle, configured to project thewash fluid toward the windshield window; a wash pump, wherein the washpump is hydraulically connected to the first hood mounted nozzle; and afirst electronic circuit, configured to estimate a position of the wiperblade during the wiper blade stroke based on an input to the firstelectronic circuit and to synchronize the projection of the wash fluidtoward the windshield window with the estimated position of the wiperblade.

In another aspect, one or more embodiments disclosed herein relate to amethod of wiping a windshield window, including operatively connecting awiper motor to a wiper blade; bringing the wiper blade in contact with awindshield window; estimating a position of the wiper blade during awiper blade stroke across the windshield window; projecting a wash fluidtoward the windshield window through a first hood mounted nozzle; andsynchronizing the projection of wash fluid toward the windshield windowwith the estimated position of the wiper blade.

In yet another aspect, one or more embodiments disclosed herein relateto a non-transitory computer readable medium comprising instructions,which, when executed by a processor, cause the processor to perform awiper blade stroke across the windshield window; estimate a position ofthe wiper blade during the wiper blade stroke; project a wash fluidtoward the windshield window through a hood mounted nozzle; andsynchronize the projection of the wash fluid toward the windshieldwindow with the estimated position of the wiper blade.

Other aspects of the disclosure will be apparent from the followingdescription and the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a windshield window wiping system for a front window of anautomotive vehicle in accordance with one or more embodiments.

FIG. 2 shows inputs to and outputs from a microprocessor of a windshieldwindow wiping system in a wiper motor assembly in accordance with one ormore embodiments.

FIG. 3 shows an electronic circuit diagram of a windshield window wipingsystem in a wiper motor assembly in accordance with one or moreembodiments.

FIG. 4 shows inputs and outputs from a microprocessor of a windshieldwindow wiping system in a wash pump motor assembly in accordance withone or more embodiments.

FIG. 5 shows an electronic circuit diagram of a windshield window wipingsystem in a wash pump motor assembly in accordance with one or moreembodiments.

FIG. 6 shows an electronic circuit diagram of a windshield window wipingsystem in a wash pump motor assembly, with pulse with modulation of awash pump, in accordance with one or more embodiments.

FIG. 7 shows inputs and outputs from a microprocessor of a windshieldwindow wiping system in a body control module in accordance with one ormore embodiments.

FIG. 8 shows an electronic circuit diagram of a windshield window wipingsystem in a body control module in accordance with one or moreembodiments.

FIG. 9 shows a timing diagram for a method of wiping a windshieldwindow, illustrating when a wash pump is turned on and off in relationto the wiper blade positions, in accordance with one or moreembodiments.

FIG. 10 shows a timing diagram for a method of wiping a windshieldwindow, illustrating pressure control of a wash pump using pulse widthmodulation, in accordance with one or more embodiments.

FIGS. 11a, 11b, 11c, and 11d show the assigned values of the wash pumptimings T1, T2, T3, and T4 in FIGS. 9 and 10 in dependency of the wipermotor supply voltage, vehicle speed, and wiper motor speed, inaccordance with one or more embodiments.

FIGS. 12a and 12b illustrate a flowchart for a method of wiping awindshield window in accordance with one or more embodiments.

FIG. 13 shows a schematic of a computing system and a non-transitorycomputer readable medium in accordance with one or more embodiments.

DETAILED DESCRIPTION

Specific embodiments will now be described in detail with reference tothe accompanying figures. Like elements in the various figures may bedenoted by like names and/or like reference numerals for consistency.

In the following detailed description of embodiments of the disclosure,numerous specific details are set forth in order to provide a morethorough understanding of the disclosure. However, it will be apparentto one of ordinary skill in the art that embodiments may be practicedwithout these specific details. In other instances, well-known featureshave not been described in detail to avoid unnecessarily complicatingthe description.

Throughout the application, ordinal numbers (e.g., first, second, third,etc.) may be used as an adjective for an element (i.e., any noun in theapplication). The use of ordinal numbers is not to imply or create aparticular ordering of the elements nor to limit any element to beingonly a single element unless expressly disclosed, such as by the use ofthe terms “before”, “after”, “single”, and other such terminology.Rather, the use of ordinal numbers is to distinguish between theelements. By way of an example, a first element is distinct from asecond element, and the first element may encompass more than oneelement and succeed (or precede) the second element in an ordering ofelements.

In general, embodiments of the present disclosure relate tocost-effective windshield window wiping of vehicles. Suchcost-effectiveness may be achieved by estimating the location of thewiper blade during the windshield window wiping and synchronizing theprojection of wash fluid with the estimated wiper blade position. Inaddition, cost-effectiveness may be achieved by smartly co-locating orcombining the additionally required elements with vehicle elements. Inone or more embodiments, windshield window wiping may be applied toautomotive vehicles. In other embodiments, windshield window wiping maybe applied to trains, ships, and airplanes. However, the presentdisclosure is not limited to these embodiments and the windshield windowwiping may be applied to other situations that require wiping ofwindows. Further, the windshield window wiping is not limited to thefront windshield window of a vehicle but may be any window (front, rear,side, top) of a vehicle. In addition, the present disclosure may alsoextend to any window of a non-vehicular structure that requires wipingof windows. Moreover, the present disclosure may also extend to anygeneral non-windowed surfaces that require wiping.

Throughout the disclosure, certain specific terms will be used todescribe elements or functionality of one or more embodiments. However,other terms may be likewise used to describe the same elements orfunctionality of one or more embodiments. For example, the term“windshield window wiping” may also be referred to as “windshieldwiping” or “window wiping” or just “wiping action.” Similarly, the term“windshield window wiper fluid” may also be referred to as “windshieldwiper fluid”, “wiper fluid”, “wash fluid”, or just “fluid.” Further,“activating/controlling a wash pump motor of a wash pump” may bereferred to as “activating/controlling a wash pump.”

FIG. 1 shows a windshield window wiping system for a front window of anautomotive vehicle in accordance with one or more embodiments. In FIG.1, element 100 depicts an automotive vehicle on which a windshieldwindow wiping system has been installed. Specifically, FIG. 1 shows apair of windshield window wipers in contact with a windshield windowduring an “Up Stroke” illustrated by arrow U and a “Down Stroke,”illustrated by arrow D. Further, FIG. 1 shows a pair of hood mountednozzles. While the automotive vehicle in FIG. 1 is shown with a pair ofwindshield window wipers and a pair of hood mounted nozzles, forsimplicity only the passenger side windshield window wiper of thewindshield window wiper pair is labeled with element 108 and discussedbelow. In addition, only the passenger side hood mounted nozzle of thepair of hood mounted nozzles is labeled with elements 120, 122, and 124,and discussed below. Further, for simplicity the operative connection ofthe wiper blade 108 to a wiper motor is not shown in FIG. 1. However,one of ordinary skill in the art would appreciate and understand thatthe wiper motor is operatively connected to the wiper blade in order toperform a wiper blade up stroke and a wiper blade down stroke. Inaddition, a reservoir for the wiper fluid as well as a wash pump toproject the wiper fluid toward the windshield window is not shown inFIG. 1.

The windshield window wiper blade in FIG. 1 has two longitudinal edges.The longitudinal edge that is furthest advanced in the direction of theup stroke is also referred to as leading edge of the wiper blade. Incontrast, the trailing edge is the longitudinal edge of the wiper bladewhich is substantially parallel to the leading edge and follows itsmovement during the up stroke. During the down stroke, the situation isreversed and the longitudinal edge that was the leading edge during theup stroke becomes the trailing edge. Similarly, during the down stroke,the longitudinal edge that was the trailing edge during the up strokebecomes the leading edge. In essence, the leading edge is thelongitudinal edge that is the furthest advanced in the direction of thewiper blade movement.

Element 108 shows the passenger side windshield window wiper bladeduring the up stroke. Specifically, FIG. 1 illustrates that during theup stroke, the windshield window wiper fluid 104 is projected from afirst nozzle 124 of the passenger side hood mount 120 toward thewindshield window in front of the leading wiper blade edge. The firstnozzle 124 of the passenger side hood mount 120 in turn is hydraulicallyconnected to a wash pump (not shown in FIG. 1). Similarly, during thedown stroke, the windshield window wiper fluid 112 is projected from asecond nozzle 122 of the passenger side hood mount 120 toward thewindshield window in front of the leading wiper blade edge. The secondnozzle 122 of the passenger side hood mount 120 in turn is hydraulicallyconnected to a wash pump (not shown in FIG. 1). During a windshieldwindow wiping the up stroke and the down stroke may be repeatedsuccessively. Consequently, the projection of windshield window wiperfluid from the first and second nozzles of the passenger side hood mount120 occur also successively in synchronization with the wiper bladestrokes. The electronic circuit required to achieve this synchronizationis discussed further below and is not shown in FIG. 1.

Although FIG. 1 has been discussed in the context of a first and secondnozzles of the passenger side hood mount 120, one of ordinary skill inthe art would know and appreciate that other embodiments of thewindshield window wiping system may utilize only a first nozzle in thepassenger side hood mount. Specifically, the use of only the firstnozzle in the passenger side hood mount may require only a single washpump while the utilization of a first and a second nozzle in thepassenger side hood mount may necessitate a reverse wash pump, a secondwash pump, or additional valves. In one or more embodiments, only afirst nozzle in the passenger side hood mount projects a wash fluidtoward the windshield window only during the up stroke or only duringthe down stroke of the windshield wiper. Further, other embodiments mayutilize other geometric openings to project the wash fluid toward thewindshield window. For example, one or more embodiments may utilizeholes or rectangular openings such as openings in the form of a slit.

Further, although FIG. 1 is shown with a pair of wiper blades and a pairof hood mounted nozzles, other embodiments may utilize only a singlewiper blade and a single hood mounted nozzle, which may include a firstnozzle and a second nozzle, or alternatively only a first nozzle. In yetother embodiments, more than two wiper blades may be used. In one ormore embodiments, the wiper blade may rotate around a pivot axis. Inother embodiments, the wiper blade may be offset from a pivot axis. Inyet further embodiments the offset from the pivot axis may not beconstant across the up stroke or the down stroke. In yet otherembodiments, the wiper blades may move in opposite directions from eachother. In other embodiments, the first and/or second nozzle may be ofdifferent size on the driver side and the passenger side. In yet otherembodiments, a shape and a wash fluid distribution of the first and/orsecond nozzle may be different on the driver side and the passengerside. Further, in additional embodiments, a shape and a wiping angle ofthe wiper blade may be different on the driver side and the passengerside. Yet other embodiments (not shown) may utilize several hood mountson the driver side and several hood mounts on the passenger side, whichmay include a single nozzle or first and second nozzles. However, one ofordinary skill in the art would know and appreciate that the presentdisclosure is not limited to the above-described geometric arrangementsand that the windshield window wiping system can be applied to any wiperarrangement. Further, one of ordinary skill in the art would know andappreciate that driver side and passenger side may be switched dependenton a target market.

In addition, while FIG. 1 has been described with a projection of thewindshield window wiper fluid 104 toward the windshield window duringthe up stroke and another projection of the windshield window wiperfluid 112 toward the windshield window during the down stroke, thepresent disclosure is not limited to these embodiments. Otherembodiments may utilize multiple projections of windshield window wiperfluid toward the windshield window during both, the up stroke and thedown stroke. Alternatively, in yet other embodiments there may bemultiple projections of windshield wiper fluid toward the windshieldwindow only during the up stroke or only during the down stroke. Yetother embodiments may optimize the windshield wiper fluid toward thewindshield window using different fluid pressure during a singleprojection or using different fluid pressure during multipleprojections. In yet other embodiments, the windshield wiper fluidpressure for a projection of wiper fluid toward the windshield windowmay vary with vehicle speed.

Referring now to FIG. 2, FIG. 2 illustrates inputs to and outputs from amicroprocessor 204 of a windshield window wiping system in accordancewith one or more embodiments. The microprocessor 204 may be a part of afirst electronic circuit. In the embodiment in FIG. 2, themicroprocessor 204 is located in a wiper motor assembly 200. Themicroprocessor 204 is configured to execute a wiper arm locationposition prediction and wash pump control algorithm. In one or moreembodiments, a measure of the supply voltage 208 to the wiper motor maybe an input to the microprocessor 204. Further, one of ordinary skill inthe art knows and appreciates that the supply voltage 208 to the wipermotor and to other components in the vehicle may vary substantially,particularly in a case where the supply voltage 208 is not regulated.One of ordinary skill in the art also knows and appreciates that onlysome components in the vehicle may receive a regulated supply voltagewhile others may receive an unregulated supply voltage.

In other embodiments, the vehicle speed 212 may be an input to themicroprocessor 204. In further embodiments, a park position signal 216may be an input to the microprocessor 204. The park position signal 216may be a reference signal for a known position of the wiper blade,provided by a wiper motor switch. For example, in some embodiments, thewiper motor switch may be an internal wiper motor limit switch which maybe closed in the park position of the wiper blade. The park position ofthe wiper blade may also be referred to as in-wipe (IW) position. Inother embodiments, the wiper motor limit switch may be closed at theother limit, i.e., at the maximum up stroke position, which is alsoreferred to as the out-wipe (OW) position of the wiper blade. In yetother embodiments, the wiper motor switch which provides a referencesignal to the microprocessor 204 may be closed at the center of the upstroke/down stroke of the wiper blade.

One of ordinary skill in the art would know and appreciate that thepresent disclosure is not limited to the described internal wiper motorlimit switch and other embodiments may utilize a different referencesignal as input to the microprocessor 204, to indicate a referenceposition of the wiper blade. For example, one or more embodiments maytrack a switching of the wiper motor poles to provide a reference signalor multiple reference signals to the microprocessor 204. Furtherembodiments may utilize various combinations of wiper motor supplyvoltage 208, vehicle speed 212, park position signal 216, and wipermotor speed 220 as inputs to the microprocessor 204. In addition, thevehicle speed input 212 may be replaced by a measurement of the wipermotor current. That is, at an increased vehicle speed, the mechanicalloading on the wiper arm and wiper blade also increases and thereforethe mechanical loading on the wiper motor increases as well. Thus, thewiper motor current measurement may replace the vehicle speed 212 asinput to the microprocessor 204. The choice of appropriate inputs may bedriven in part by how strongly the specific input affects the wipermotor speed and the cost-adder associated with each input.

In FIG. 2, the various inputs to the microprocessor 204 are indicatedwith arrows of different length. The start of the arrows of the supplyvoltage input 208 and park position signal input 216 are located insidethe schematic box of the wiper motor assembly 200. In contrast, thestart of the arrows of the vehicle speed input 212 and wiper motor speedinput 220 are located outside the schematic box of the wiper motorassembly 200. Specifically, the start of the respective arrow indicateswhether the specific input has to be provided from externally to thewiper motor assembly or whether it may be available from within thewiper motor assembly. One of ordinary skill in the art knows andappreciates that the cost-adder may be less in a case where therespective input is available from within the wiper motor assembly. Withrespect to FIG. 2, the supply voltage 208 and the park position signal216 are available within the wiper motor assembly 200, while the vehiclespeed 212 and the wiper motor speed 220 may have to be provided fromexternally to the wiper motor assembly.

In the embodiment in FIG. 2, an output of the microprocessor 204 may bea signal 224 to activate a primary wash pump. In one or moreembodiments, the primary wash pump may be hydraulically connected to afirst nozzle of a hood mount. In other embodiments, a further output ofthe microprocessor 204 may be a signal 228 to activate a second washpump. In one or more embodiments, the second wash pump may behydraulically connected to a second nozzle of the hood mount. In yetother embodiments, a reversible wash pump may be activated in forward orreverse. In one or more embodiments, the reversible wash pump may beconnected in forward to the first nozzle of the hood mount, and inreverse to the second nozzle of the hood mount. In yet otherembodiments, the microprocessor 204 may provide output to a wash pumpand one or more valves, which are hydraulically connected to the firstand second nozzles of the hood mount. As discussed above, the presentdisclosure is not limited to nozzles of a hood mount and otherembodiments may utilize other geometric openings to project the washfluid toward the windshield window. For example, one or more embodimentsmay utilize holes or rectangular openings such as openings in the formof a slit. Yet other embodiments may utilize shaped nozzles in lieu ofholes.

FIG. 3 shows an electronic circuit diagram of a windshield window wipingsystem in a wiper motor assembly 300 corresponding to FIG. 2. Inaccordance with one or more embodiments, a microprocessor 304 is locatedwithin the wiper motor assembly 300. In FIG. 3, the microprocessor 304is provided with a regulated voltage 356 of 5V from the voltageregulator 312. However, the present disclosure is not limited to aregulated voltage 356 of 5V and other embodiments may use regulatedvoltages lower or higher than 5V. In addition, several inputs areavailable to the microprocessor 304. One of these inputs is a voltagemeasure circuit 308, which measures the supply voltage. FIG. 3 alsoillustrates that the supply voltage 348 is also the voltage of the wipermotor 328. In one or more embodiments, the supply voltage 348 may be onthe order of 13.5V. In other embodiments, the supply voltage 348 may belarger or smaller than 13.5V and may vary dependent on an alternatoroutput voltage. Further, one of ordinary skill in the art knows andappreciates that the present disclosure is not limited to the particularvoltage measure circuit 308 shown in FIG. 3. In one or more embodiments,the supply voltage 348 may be measured by a different voltage measurecircuit.

Another input to the microprocessor 304 in FIG. 3 may be wiper commands360 and the vehicle speed 364. The wiper commands 360 and the vehiclespeed 364 may be provided to the microprocessor 304 by a localinterconnect network (LIN) interface 316. The LIN interface 316 receivesinformation from a serial data bus 352 and utilizes a serial networkprotocol for exchange of information between components. In FIG. 3, thewiper commands 360 provided by the LIN interface 316 to themicroprocessor 304 may contain information whether the low speed or highspeed wiper motor speed has been selected by the vehicle operator.Further, the wiper commands 360 may indicate whether the vehicleoperator has selected to clean the windshield window. However, thepresent disclosure is not limited to a LIN interface 316. In one or moreembodiments, the LIN interface 316 may be replaced with a controllerarea network (CAN) bus. In yet other embodiments, the LIN interface 316may be replaced with a wireless transmission. In yet other embodiments,the LIN interface 316 may be replaced by hardwiring of inputs to themicroprocessor 304.

A further input to the microprocessor 304 in FIG. 3 may be a park signal368, also referred to as park position signal or as park signal input.As described above, the park position signal 368 may be a referencesignal for a known position of the wiper blade, provided by a wipermotor switch 324. Specifically, a wiper motor 328 is shown in FIG. 3 andFIG. 3 further illustrates that the wiper blade position 394 affects theclosure of a wiper motor switch 324. In FIG. 3, the wiper motor switch324 is shown external to the wiper motor 328. In other embodiments, thewiper motor switch 324 may be internal to the wiper motor 328. In a casewhen the wiper motor switch 324 is in a “Park” position 372, the wiperblades are in the corresponding in-wipe (IW) position, which is alsoreferred to as a known reference position of the wiper blades. In thiscase, a reference signal for the known position of the wiper blades isprovided as input to the microprocessor 304. Specifically, the parksignal input 368 to the microprocessor 304 is pulled to ground when thewiper motor switch 324 is in the “Park” position 372. In a case when thewiper motor switch 324 is in a “Run” position 376, the wiper blades areeither in the up stroke, at the out-wipe (OW) position, or in the downstroke, but not in the IW position. In this case, the park signal input368 to the microprocessor 304 is pulled “high” to the power supplyvoltage 348 via the pull-up resistor 320.

Still referring to FIG. 3, the microprocessor 304 may have severaloutputs. For example the microprocessor 304 may affect the position ofthe low speed/high speed switch 332 indicated by the dotted lines inFIG. 3. The low speed position of the low speed/high speed switch 332 inFIG. 3 is indicated by the numeral 384, while the high speed position isindicated by the numeral 380. In addition, the microprocessor 304 mayaffect the position of the On/Off switch 336. The On position of theOn/Off switch 336 in FIG. 3 is indicated by the numeral 388, while theOff position is indicated by the numeral 392. Further, themicroprocessor 304 may affect the position of a wash pump switch 344,which in turn activates power to a wash pump for the “Up Wash” 398. Inone or more embodiments, the “Up Wash” refers to the projection ofwindshield wiper fluid toward the windshield window during the up stroke(i.e. projection through the up ramp). Similarly, in one or moreembodiments, the “Down Wash” refers to the projection of windshieldwiper fluid toward the windshield window during the down stroke (i.e.projection through the down ramp). FIG. 3 also illustrates that themicroprocessor 304 may further affect the position of the switch 340,which in turn may activate power to another wash pump for the down wash396. However, as described above, the present disclosure is not limitedby these embodiments. Alternate embodiments as described above, mayutilize only a single wash pump, a primary and a secondary wash pump, ora single wash pump with an added valve or valves. Further, otherembodiments may utilize multiple projections of windshield window wiperfluid toward the windshield window during both, the up stroke and thedown stroke. Alternatively, in yet other embodiments there may bemultiple projections of windshield wiper fluid toward the windshieldwindow only during the up stroke or only during the down stroke. Yetother embodiments may optimize the windshield wiper fluid toward thewindshield window using different fluid pressure during a singleprojection or using different fluid pressure during multipleprojections. In yet other embodiments, the windshield wiper fluidpressure for a projection of wiper fluid toward the windshield windowmay vary with vehicle speed.

FIG. 4 illustrates inputs and outputs from a microprocessor 404 of awindshield window wiping system in a wash pump motor assembly 400 inaccordance with one or more embodiments. For the sake of brevity, onlythe differences to FIG. 2 will be explained. However, all variations andalternate embodiments described with respect to FIG. 2 are alsoapplicable to FIG. 4 as well. In FIG. 4, the microprocessor 404 may be apart of a first electronic circuit. In the embodiment in FIG. 4, themicroprocessor 404 is located in a wash pump motor assembly 400. Placingthe first electronic circuit into the wash pump motor assembly 400 maybe advantageous from a cost-perspective because the supply voltage 408of the wiper motor, which is essentially the supply voltage of the washpump, is readily available inside the wash pump motor assembly 400.Other potential inputs to the microprocessor 404 may be combinations ofvehicle speed 412, park position signal 416, and wiper motor speed 420,which may have to be provided from externally to the wash pump motorassembly. In the embodiment in FIG. 4, an output of the microprocessor404 may be a signal 424 to activate a primary wash pump. In otherembodiments, a further output of the microprocessor 404 may be a signal428 to activate a second wash pump.

FIG. 5 shows an electronic circuit diagram of a windshield window wipingsystem in a wash pump motor assembly 500 corresponding to FIG. 4. Inaccordance with one or more embodiments, a microprocessor 504 is locatedwithin the wiper motor assembly 500 indicated by a dotted line. For thesake of brevity, only the differences to FIG. 3 will be explained.However, all variations and alternate embodiments described with respectto FIG. 3 are also applicable to FIG. 5 as well. In FIG. 5, themicroprocessor 504 may be a part of a first electronic circuit. Incontrast to FIG. 3, FIG. 5 does not show the wiper motor, low speed/highspeed switch, and On/Off switch, because in the embodiment in FIG. 5,these components are located outside the wash pump motor assembly 500.However, FIG. 5 indicates that a LIN interface 516 provides the parksignal input to the microprocessor 504 along with the previouslydescribed wiper commands and vehicle speed input.

In FIG. 5, the microprocessor 504 is provided with a regulated voltage556 of 5V from the voltage regulator 512. However, the presentdisclosure is not limited to a regulated voltage 556 of 5V and otherembodiments may use regulated voltages lower or higher than 5V. Inaddition, several inputs are available to the microprocessor 504. One ofthese inputs is a voltage measure circuit 508, which measures the supplyvoltage. In one or more embodiments, the supply voltage 548 may be onthe order of 13.5V. In other embodiments, the supply voltage 548 may belarger or smaller than 13.5V and may vary dependent on an alternatoroutput voltage. Further, one of ordinary skill in the art knows andappreciates that the present disclosure is not limited to the particularvoltage measure circuit 508 shown in FIG. 5. In one or more embodiments,the supply voltage 548 may be measured by a different voltage measurecircuit.

Another input to the microprocessor 504 in FIG. 5 may be wiper commands560, the park signal 568, and the vehicle speed 564. The wiper commands560, the park signal 568, and the vehicle speed 564 may be provided tothe microprocessor 354 by a local interconnect network (LIN) interface516. The LIN interface 516 receives information from a serial data bus552 and utilizes a serial network protocol for exchange of informationbetween components. In FIG. 5, the wiper commands 560 provided by theLIN interface 516 to the microprocessor 504 may contain informationwhether the low speed or high speed wiper motor speed has been selectedby the vehicle operator. Further, the wiper commands 560 may indicatewhether the vehicle operator has selected to clean the windshieldwindow. The microprocessor 504 may affect the position of a wash pumpswitch 524, which in turn activates power to a wash pump for the up wash598. The microprocessor 504 may further affect the position of theswitch 520, which in turn may activate power to another wash pump forthe down wash 596.

FIG. 6 illustrates an electronic circuit diagram of a windshield windowwiping system in a wash pump motor assembly 600, with pulse withmodulation of a wash pump, in accordance with one or more embodiments.Several components in FIG. 6 are similar to FIG. 5, e.g. the voltagemeasure circuitry 608 for the supply voltage, the voltage regulator 612,the regulated voltage 656, the LIN interface 616, the wiper commands660, the park signal 668, and the vehicle speed 664 within the wash pumpmotor assembly 600. Further, FIG. 6 illustrates the supply voltage 648,the serial bus 652, the output to a wash pump for the up wash 698, andthe output for a wash pump for the down wash 696. However, FIGS. 5 and 6differ in that in FIG. 6, the microprocessor 604 controls the wash pumpmotor of the a wash pump or multiple wash pumps via a second electroniccircuit 620. The second electronic circuit 620 in FIG. 6 may also belocated within the wash pump motor assembly 600. Controlling the washpump motor or multiple wash pump motors with pulse width modulation(PWM) advantageously allows to dynamically adjusting the pressure of theprojected wash fluid toward the windshield window during a wiper stroke.In one or more embodiments, the PWM of the wash pump motor or multiplewash pump motors may be performed by a MOSFET driver. In otherembodiments, the PWM of the wash pump motor or multiple wash pump motorsmay be performed by a different driver. However, the present disclosureis not limited to pulse width modulation of the wash pump motor ormultiple wash pump motors. Other embodiments may utilize othertechniques to dynamically control the pressure of the projected washfluid. In one or more embodiments, the supply voltage to the wash pumpmotor or multiple wash pump motors may be dynamically controlled toaffect the wash fluid pressure during projection toward the windshieldwindow. In yet other embodiments, the wash pump motor may utilize astepper motor and the microprocessor 604 may dynamically adjust thepressure of the wash fluid by controlling the number of stepper motorsteps executed per unit time. Yet other embodiments may utilize otherwash pump motor control techniques that differ from the wash pump motorcontrols discussed above.

In addition, with respect to dynamic pressure control of the projectedwash fluid illustrated in FIG. 6, one or more embodiments may utilizeonly a first nozzle of a hood mount and the wash fluid may be projectedfrom the first nozzle toward the windshield window with lower pressureduring the up stroke and with higher pressure during the down stroke.Therefore, at lower pressure, the wash fluid may be projected at a lowerlocation on the windshield window in front of the leading edge of thewiper blade during the up stroke. Similarly, at higher pressure, thewash fluid may be projected at a higher location on the windshieldwindow in front of the leading edge of the wiper blade during the downstroke. Alternatively, other embodiments may utilize only a first nozzleof a hood mount in combination with a fluid restriction valve.Specifically, the fluid restriction valve may result in a pressure dropof the wash fluid and may be activated to project the wash fluid at alower location on the windshield window in front of the leading edge ofthe wiper blade during the up stroke. For the down stroke, the fluidrestriction valve may be deactivated and the wash fluid may be projectedat a higher location on the windshield window in front of the leadingedge of the wiper blade during the down stroke.

FIG. 7 shows inputs and outputs from a microprocessor of a windshieldwindow wiping system in a body control module (BCM) 700 in accordancewith one or more embodiments. A BCM is an electronic control unit forvarious components and functions in a vehicle. For the sake of brevity,only the differences to FIGS. 2 and 4 will be explained. However, allvariations and alternate embodiments described with respect to FIGS. 2and 4 are also applicable to FIG. 7 as well. In FIG. 7, themicroprocessor 704 may be a part of a first electronic circuit. In theembodiment in FIG. 7, the microprocessor 704 is located in the BCM 700.Placing the first electronic circuit into the BCM 700 may beadvantageous from a cost-perspective because the supply voltage 708 ofthe wiper motor, which is essentially the supply voltage of the washpump, is readily available inside the BCM 700. In addition, otherpotential inputs to the microprocessor 704 may be the vehicle speed 712and the wiper motor speed 720, which are already available inside theBCM 700. Another potential input to the microprocessor 704 may be thepark position signal 716, which may have to be provided from externallyto the BCM 700. In the embodiment in FIG. 7, an output of themicroprocessor 704 may be a signal 724 to activate a primary wash pump.In other embodiments, a further output of the microprocessor 704 may bea signal 728 to activate a second wash pump.

Referring now to FIG. 8, FIG. 8 illustrates an electronic circuitdiagram of a windshield window wiping system in a body control module(BCM) in accordance with one or more embodiments. Specifically, FIG. 8shows vehicle relays 852 as well as electronic components in the BCM 800and in the wiper motor assembly 828. In accordance with one or moreembodiments, a microprocessor 804 is located within the BCM 800. For thesake of brevity, only the differences to FIGS. 3, 5, and 6 will beexplained. However, all variations and alternate embodiments describedwith respect to FIGS. 3, 5, and 6 are also applicable to FIG. 8 as well.In FIG. 8, the microprocessor 804 may be a part of a first electroniccircuit. Several components in FIG. 8 are similar to FIGS. 3, 5, and 6,e.g. the voltage measure circuitry 808 for the supply voltage, thevoltage regulator 812, the regulated voltage 856, the LIN interface 816,the wiper commands 860, and the vehicle speed 864 within the BCM 800.Also, the park position signal input 868 and the pull-up resistor 820are provided in the BCM 800. Further, FIG. 8 illustrates the supplyvoltage 848 and the serial data bus 852. As previously discussed withrespect to FIG. 7, when the microprocessor 704 is located within the BCM700, then the park position signal may need to be provided fromexternally to the BCM 700. Accordingly, FIG. 8 illustrates the locationof the wiper motor 832 and the wiper motor switch 824 in the wiper motorassembly 828, the wiper motor switch 824 providing the park positionsignal to the microprocessor 804 in the BCM 800. The wiper motor switch824 may have a “park” position 872 and a “run” position 876 and theblade position 894 may affect the “park” or “run” position of the wipermotor switch 824. In one or more alternative embodiments, the parkposition signal may be provided to the microprocessor 804 via the LINinterface 816. In yet other embodiments, the park position signal may bewirelessly provided to the microprocessor 804.

FIG. 8 further shows vehicle relays 852 which are driven by outputs ofthe microprocessor 804. For example, relay 836 may select between lowspeed 884 and high speed 880 wiper motor operation. In addition, themicroprocessor 804 may affect the On position 888 and Off position 892of relay 840. Further, the microprocessor 804 may affect the position ofa wash pump relay 848, which in turn activates power to a wash pump forthe up wash 898. FIG. 8 also illustrates that the microprocessor mayfurther affect the position of the relay 844, which in turn may activatepower to another wash pump for the down wash 896. One of ordinary skillin the art knows and appreciates that driving relays from the output ofa microprocessor 804 is one option of controlling vehicle components.Other embodiments may utilize power transistors instead of relays tocontrol vehicle components. In yet other embodiments, the controlling ofvehicle components may be achieved by pulse width modulation. However,the present disclosure is not limited to these particular embodimentsand other embodiments may utilize different approaches of controllingvehicle components by the microprocessor 804.

FIG. 9 shows a timing diagram for a method of wiping a windshieldwindow, illustrating when a wash pump is turned on and off in relationto the wiper blade positions, in accordance with one or moreembodiments. Specifically, FIG. 9 refers to a timing diagram for an “upwash” 904 and a timing diagram for a “down wash” 908. In one or moreembodiments, the “up wash” 904 refers to the projection of windshieldwiper fluid toward the windshield window during the up stroke.Similarly, in one or more embodiments, the “down wash” 908 refers to theprojection of windshield wiper fluid toward the windshield window duringthe down stroke. In FIG. 9, “IW” refers to the windshield wiper in-wipeposition, while “OW” refers to the windshield wiper out-wipe position.As mentioned before, in one or more embodiments, the IW position of thewiper blade may also be referred to as park position of the wiper blade.Further, the OW position of the wiper blade may also be referred to asthe maximum up stroke position. At the IW position of the wiper blade,the time is set to zero.

Still referring to FIG. 9, in one or more embodiments, T1 denotes a timewhich starts when the wiper blade is in the park position (but is justabout to start the up stroke across the windshield window) and ends whena first wash pump has been turned on. In one or more embodiments, theturned on first wash pump projects wash fluid toward the windshieldwindow, specifically in front of the just starting to move wiper blade.While the wiper blade moves across the windshield window toward the OWposition, the first wash pump continues to project wash fluid toward thewindshield window in front of the wiper blade until time T2 has beenreached. At time T2, the first wash pump is switched off and the wiperblade continues the up stroke toward the OW position. At time T3, thewiper blade has already reached the OW position and has started to beginthe down stroke toward the IW position (park position). In one or moreembodiments, a second wash pump is turned on at time T3 and the secondwash pump projects wash fluid toward the windshield window, specificallyin front of the moving wiper blade. While the wiper blade moves acrossthe windshield window toward the IW position, the second wash pumpcontinues to project wash fluid toward the windshield window in front ofthe wiper blade until time T4 has been reached. At time T4, the secondwash pump is switched off and the wiper blade continues the down stroketoward the IW position. The time interval between the time when thewiper blade is initially in the IW position to the time when the wiperblade returns to the IW position is also referred to as wipe period 900.Once the wipe period 900 has elapsed, the timing diagram starts from thebeginning until a predetermined number of wipe periods 900 has beenachieved.

In one or more embodiments the predetermined number of wipe periods istwo. In other embodiments, the predetermined number is a single wipeperiod. In yet other embodiments, the predetermined number is more thantwo wipe periods. However, as described above, the present disclosure isnot limited by these embodiments. Alternate embodiments may utilize onlya single wash pump, a primary and a secondary wash pump, or a singlewash pump with an added valve or valves. Further, other embodiments mayutilize multiple projections of windshield window wiper fluid toward thewindshield window during both, the up stroke and the down stroke.Alternatively, in yet other embodiments there may be multipleprojections of windshield wiper fluid toward the windshield window onlyduring the up stroke or only during the down stroke. Yet otherembodiments may optimize the windshield wiper fluid toward thewindshield window using different fluid pressures during a singleprojection or using different fluid pressure during multiple projectionsas shown in FIG. 10. The different fluid pressures during a singleprojection are also referred to as fluid pressure profile.

FIG. 10 shows a timing diagram for a method of wiping a windshieldwindow, illustrating pressure control of a wash pump using pulse widthmodulation, in accordance with one or more embodiments. Specifically,FIG. 10 refers to a timing diagram for an “up wash” 1004 and a timingdiagram for a “down wash” 1008. The time interval between the time whenthe wiper blade is initially in the IW position to the time when thewiper blade returns to the IW position is also referred to as wipeperiod 1000. For the sake of brevity, only the differences to FIG. 9will be explained. However, all variations and alternate embodimentsdescribed with respect to FIG. 9 are also applicable to FIG. 10 as well.As described above, controlling the wash pump motor or multiple washpump motors with pulse width modulation (PWM) advantageously allows todynamically adjusting the pressure of the projected wash fluid towardthe windshield window during a wiper stroke. The varied pressure of theprojected wash fluid, i.e. the fluid pressure profile, is indicated inFIG. 10 as a pressure decrease (vertical difference for wash pump “on”in timing diagram) at time T1 and ending at T2 during the up wash andstarting at time T3 and ending at time T4 during the down wash. However,the present disclosure is not limited to pulse width modulation of thewash pump motor or multiple wash pump motors. Other embodiments mayutilize other techniques to dynamically control the pressure of theprojected wash fluid as described in reference to FIG. 6. Further, inone or more embodiments, the fluid pressure profile may be differentdepending on the vehicle speed.

In accordance with one or more embodiments of the method of wiping awindshield window, FIGS. 11a, 11b, 11c, and 11d show the assigned valuesof the wash pump timings T1 (up stroke, wash pump on/“Up Wash ON”), T2(up stroke, wash pump off/“Up Wash OFF”), T3 (down stroke, wash pumpon/“Down Wash ON”), and T4 (down stroke, wash pump off/“Down Wash OFF”)in FIGS. 9 and 10 in dependency of the wiper motor supply voltage,vehicle speed, and wiper motor speed, in accordance with one or moreembodiments. Specifically, FIGS. 11a, 11b, 11c, and 11d show the wipermotor supply voltage vertically, and the vehicle speed horizontally. Adivision between low and high wiper motor speed is also provided on thehorizontal axis. The wash pump timings in FIGS. 11a, 11b, 11c, and 11dare in milliseconds (ms).

As can be seen from FIG. 11a , the assigned time T1 decreases withincreasing vehicle speed. The same is valid for the assigned times T2,T3, and T4 in FIGS. 11b, 11c, and 11d . The reason for the decreasedassigned time for increased vehicle speeds is, because the wiper motorspeed increases for increased vehicle speeds due to increased wind dragon the wiper blades. Consequently, a smaller time is needed at a highvehicle speed for the wiper blade to reach the same position whencompared to a larger time at low vehicle speed. As can further be seenfrom FIG. 11a , the assigned time T1 is smaller for the high wiper speedwhen compared to the low wiper speed. Assigned times T2, T3, and T4 inFIGS. 11b, 11c, and 11d behave similarly. This is, because at high wiperspeed, the wash pump or several wash pumps have to be turned on (andoff) faster when compared to the low wiper speed to reach the same wiperblade position.

In addition, it can be seen from FIGS. 11a, 11b, 11c, and 11d , that theassigned times T1 through T4 are smaller with increasing wiper motorsupply voltage. This is the results of that at higher wiper motor supplyvoltages, the wiper motor speed increases and consequently a smallertime is needed at high wiper motor supply voltage for the wiper blade toreach the same position when compared to a smaller wiper motor supplyvoltage. However, the present disclosure is not limited to the assignedtimes T1, T2, T3, and T4 in respective FIGS. 11a, 11b, 11c, and 11d . Inone or more embodiments, the assigned times may be larger or smallerthan the assigned times T1, T2, T3, and T4 in respective FIGS. 11a, 11b,11c, and 11d . In other embodiments, the assigned times may not decreasemonotonously with increasing wiper motor supply voltage, increasingvehicle speed and at the low or high wiper motor speed setting. Otherembodiments may utilize a smaller set of assigned timings, for example,in the case when only a single wash pump is used. Additional embodimentsmay contain a larger set of assigned timings, for example, in the casewhen multiple projections of windshield wiper fluid toward thewindshield window during the up stroke or during the down stroke areused. In yet other embodiments, the assigned timings may be adjusted forthe utilization of varied wash fluid pressure during a single projectionor during multiple wash fluid projections toward the windshield window.

In yet additional embodiments, the assigned timings for a specificvehicle or vehicle configuration may be determined empirically,semi-empirically, from theoretical calculations or from simulations.Further, the assigned timings may be measured or estimated under actualdriving conditions. For example, the position of the wiper blade acrossthe windshield window may be measured at fixed time intervals startingat time=0 for when the wiper blade is in the IW position and theinternal wiper blade switch is closed. The position of the wiper bladeacross the windshield window may be measured for various vehicle speeds,wiper motor supply voltages, and for the high/low wiper motor speedconditions. From the measured positions of the wiper blade across thewindshield window at fixed time intervals, the timings can be calculatedfor when the wash pump or wash pumps must be turned on and off.Specifically, in one or more embodiments, the “on” and “off” timing forthe wash pump may be selected such that the wash fluid is projected infront of the leading edge of the wiper blade.

Alternatively, the assigned timings may be measured or estimated in awind tunnel. For example the vehicle velocity may be simulated in a windtunnel by adjusting the flow of air in the wind tunnel to be equal tothe intended vehicle speed. In addition, a high-speed camera may bedirected at the windshield window and may record the position of thewindshield wiper across the windshield window at known fixed timeintervals starting at time=0 for when the wiper blade is in the IWposition and the internal wiper blade switch is closed. Further, duringthe wind tunnel measurements, the wiper motor supply voltage may be“simulated” by manually adjusting the wiper motor supply voltage from anexternal power source. As described above, from the evaluated cameraimages of the positions of the wiper blade across the windshield windowat known time intervals, the timings to turn the wash pump on and offcan be selected such that the wash fluid is projected in front of theleading edge of the wiper blade. However, the present disclosure is notlimited to these embodiments and the timings to turn on and off the washpump or wash pumps may be selected such as that the wash fluid isprojected in front, behind, or both in front and behind the leading edgeof the wiper blade.

In one or more embodiments, a suitable mathematical expression may befitted to the calculated or estimated wash pump timing values as afunction of input parameters, such as the wiper motor supply voltage,vehicle speed, high/low wiper motor speed, etc. In other embodiments,the determined position of the wiper blade across the windshield windowas a function of time may be fitted with a suitable mathematicalfunction. Regardless of whether a mathematical expression is fitted tothe timing values or to the position of the wiper blade as a function ofthe above referenced input parameters, the wash pump or wash pumps needto be turned on or off at the appropriate time or wiper position and onecan be converted into the other and vice versa.

In other embodiments, a fractional factorial or full factorialdesign-of-experiments (DOE) may be executed to determine whether anyinteractions exist between the input parameters. A full factorial DOErefers to that the wiper blade position on the windshield window forknown fixed time intervals starting at time=0 (IW position) isdetermined for all combinations of input parameters. In contrast, afractional factorial DOE may be performed when it is certain that somecombinations of input parameters do not significantly affect the wiperblade position. The determination of when the wash pump or wash pumpsneed to be turned on or off may only need to be determined once for aparticular vehicle or vehicle configuration. In one or more embodiments,a correction factor may be used to compensate for any aging of thewindshield wiper motor, alternator, or other components of the vehicle.In other embodiments, a value may enter the timing calculationsreflecting whether the wiper blade has just been replaced. That is,because in one or more embodiments, the position of the wiper blade onthe windshield window may be affected by friction between the leadingedge of the wiper blade and the windshield window. As wear occurs on thewiper blade over time, the friction between the leading edge of thewiper blade and the windshield window may change over time and in turnmay affect the position of the wiper blade on the windshield window.

FIGS. 12a and 12b illustrate a flowchart for a method of wiping awindshield window in accordance with one or more embodiments. In one ormore embodiments, the method of wiping a windshield window includesconnecting a wiper motor operatively to a wiper blade and bringing thewiper blade in contact with a windshield window. Further, the method ofwiping a windshield window may also include estimating a position of thewiper blade during a wiper blade stroke across the windshield window. Inaddition, the method may include projecting a wash fluid toward thewindshield window through a first nozzle of a hood mount andsynchronizing the projection of wash fluid toward the windshield windowwith the estimated position of the wiper blade. In other embodiments,the method of wiping a windshield window may further include projectinga wash fluid toward the windshield window through a second nozzle of ahood mount, wherein the first nozzle of the hood mount and the secondnozzle of the hood mount sequentially project the wash fluid toward thewindshield window during an up stroke and a down stroke of the wiperblade.

Further, with respect to dynamic pressure control of the projected washfluid, one or more embodiments may utilize only a first nozzle of a hoodmount and the wash fluid may be projected from the first nozzle towardthe windshield window with lower pressure during the up stroke and withhigher pressure during the down stroke. Therefore, at lower pressure,the wash fluid may be projected at a lower location on the windshieldwindow in front of the leading edge of the wiper blade during the upstroke. Similarly, at higher pressure, the wash fluid may be projectedat a higher location on the windshield window in front of the leadingedge of the wiper blade during the down stroke. Alternatively, otherembodiments may utilize only a first nozzle of a hood mount incombination with a fluid restriction valve. Specifically, the fluidrestriction valve may result in a pressure drop of the wash fluid andmay be activated to project the wash fluid at a lower location on thewindshield window in front of the leading edge of the wiper blade duringthe up stroke. For the down stroke, the fluid restriction valve may bedeactivated and the wash fluid may be projected at a higher location onthe windshield window in front of the leading edge of the wiper bladeduring the down stroke.

Specifically, the method of wiping a windshield window in accordancewith one or more embodiments starts at 1200. At 1204 it is verifiedwhether a wash spray button has been pressed by a vehicle operator. Ifthe wash spray button has not been pressed by the vehicle operator, themethod keeps checking whether the wash spray button has been pressed. Inthe event that the wash spray button has been pressed by the vehicleoperator at 1204, the method continues to 1208 at which it is nextverified whether the wiper motor is already turned on by the vehicleoperator. This verification at 1208 distinguishes between a first casein which the wiper motor is not yet running, e.g. because it is sunnybut the operator has pressed the wash spray button to clean thewindshield window and a second case in which the wiper motor is alreadyrunning, e.g. because of rain and the operator has pressed the washspray button to clean the windshield.

In the first case the method continues to 1212 at which a low wipermotor speed is selected. The method then proceeds to 1216 at which thesupply voltage to the wiper motor is determined. Next, the methodcontinues at 1220 at which the vehicle speed is determined. Once, thewiper motor speed is selected and the supply voltage to the wiper motorand the vehicle speed are known, the method continues at 1224 at whichtiming values for T1, T2, T3, T4 are obtained from one or more lookuptables for the particular combination of wiper motor speed wiper motorsupply voltage, and vehicle speed. The method then proceeds to 1228 atwhich the wiper motor is turned on at low speed in accordance with theselected low wiper motor speed at 1212. The method continues at 1232 atwhich a timer is reset and started. Specifically, the timer measures thetime with respect to FIGS. 9 and 10 starting from the in-wipe (IW)position of the wiper blade when an internal wiper motor switch isclosed. Once the timer has been started at 1232 and the wiper bladestarts the up stroke, the method continues to 1236 at which a primarywash pump is activated (turned on) when the timer reaches the time T1.As a result of the wash pump activation at time T1, wash spray isprojected toward the windshield window in front of the leading edge ofthe wiper blade.

The method then proceeds to 1240 at which the primary wash pump isdeactivated (turned off) when the timer reaches the time T2. Once theprimary wash pump is turned off, the projection of wash spray toward thewindshield window is stopped and the wiper blade continues the upstroke. Once the wiper blade reaches the out-wipe (OW) position, thewiper blade starts the down stroke. The method continues at 1244 atwhich the down stroke has just started and the secondary wash pump isactivated when the timer reaches the time T3. As a result of the washpump activation at time T3, wash spray is projected toward thewindshield window in front of the leading edge of the wiper blade. Themethod then proceeds to 1248 at which the secondary wash pump isdeactivated (turned off) when the timer reaches the time T4. Once thesecondary wash pump is turned off, the projection of wash spray towardthe windshield window is stopped and the wiper blade continues the downstroke

The method then continues at 1252 at which it is verified whether theinternal wiper motor switch is closed, i.e. when the wiper blade hascontinued the down ramp and has reached the IW position again. If theinternal wiper motor switched is not closed at 1252, the methodcontinues verifying whether the internal wiper motor switch is closed.In case the internal wiper motor switch is closed at 1252, the methodproceeds to 1256 at which the wiper motor is turned off when the whenthe wiper blade has reached the IW position again. Once the wiper motoris turned off at 1256, the method continues at 1204 at which it is onceagain verified whether a wash spray button has been pressed by a vehicleoperator.

As previously mentioned, the verification at 1208 distinguishes betweena first case in which the wiper motor is not yet running, e.g. becauseit is sunny but the operator has pressed the wash spray button to cleanthe windshield window and a second case in which the wiper motor isalready running, e.g. because of rain and the operator has pressed thewash spray button to clean the windshield.

In the second case the method continues to 1260 at which it isdetermined based on the wiper motor low/high switch, whether the vehicleoperator has set the wiper motor speed to the low speed setting or tothe high speed setting. The method then proceeds to 1264 at which thesupply voltage to the wiper motor is determined. Next, the methodcontinues at 1268 at which the vehicle speed is determined. Once, thewiper motor speed set by the operator is determined and the supplyvoltage to the wiper motor and the vehicle speed are known, the methodcontinues at 1272 at which timing values for T1, T2, T3, T4 are obtainedfrom one or more lookup tables for the particular combination of wipermotor speed wiper motor supply voltage, and vehicle speed. The methodthen proceeds to 1276 at which it is verified whether the internal wipermotor switch is closed. Since the wiper motor is already running asdetermined at 1208, the method verifies at 1276 when the wiper blade isin the IW position, i.e. when the internal wiper motor switch is closed.If the internal wiper motor switch is not closed at 1276, the methodcontinues checking whether the internal wiper motor switch is closed.

If the internal wiper motor switch is closed, the method proceeds to1280 at which a timer is reset and started. As described above, thetimer measures the time with respect to FIGS. 9 and 10 starting from thein-wipe (IW) position of the wiper blade when an internal wiper motorswitch is closed. Once the timer has been started at 1280 and the wiperblade starts the up stroke, the method continues to 1284 at which aprimary wash pump is activated (turned on) when the timer reaches thetime T1. As a result of the wash pump activation at time T1, wash sprayis projected toward the windshield window in front of the leading edgeof the wiper blade.

The method then proceeds to 1288 at which the primary wash pump isdeactivated (turned off) when the timer reaches the time T2. Once theprimary wash pump is turned off, the projection of wash spray toward thewindshield window is stopped and the wiper blade continues the upstroke. Once the wiper blade reaches the out-wipe (OW) position, thewiper blade starts the down stroke. The method continues at 1292 atwhich the down stroke has just started and the secondary wash pump isactivated when the timer reaches the time T3. As a result of the washpump activation at time T3, wash spray is projected toward thewindshield window in front of the leading edge of the wiper blade. Themethod then proceeds to 1296 at which the secondary wash pump isdeactivated (turned off) when the timer reaches the time T4. Once thesecondary wash pump is turned off, the projection of wash spray towardthe windshield window is stopped and the wiper blade continues the downstroke. Once the secondary wash pump is turned off at 1296, the methodcontinues at 1204 at which it is once again verified whether a washspray button has been pressed by a vehicle operator.

Still referring to FIGS. 12a and 12b , it was described above that themethod verifies at 1208 whether the wiper motor is already turned on bythe vehicle operator. Subsequently, this verification at 1208distinguishes between a first case in which the wiper motor is not yetrunning, e.g. because it is sunny but the operator has pressed the washspray button to clean the windshield window and a second case in whichthe wiper motor is already running, e.g. because of rain and theoperator has pressed the wash spray button to clean the windshield. Inthe first case, the method proceeds with 1212 through 1256 while in thesecond case, the method continues with a parallel path 1260 through 1296before rejoining again at 1204. The difference between these twoparallel paths is that in the first case, the wiper motor is not runningyet and needs to be turned on and turned off. In contrast in the secondcase, the wiper motor is already running and the method needs todetermine at which speed the wiper motor is running and when the wiperblade is in the IW position. Once the second case completes the path1260 through 1296, the wiper motor remains running (i.e. because ofinclement weather) until the vehicle operator eventually switches thewiper motor off.

However, the present disclosure is not limited to the embodimentdescribed with respect to the method flowchart in FIGS. 12a and 12b .One of ordinary skill in the art knows and appreciates that the methodof wiping a windshield window could be realized differently. Forexample, in one or more embodiments, the method does not have to remainat 1204 until the wash spray button is pressed by the vehicle operator.Specifically, the method may check periodically at 1204 whether the washspray button has been pressed by the vehicle operator. Meanwhile, whilethe method is not actively checking at 1204, the method may continuedoing other activities. Of course, the time between periodic checking at1204 may be chosen small enough as to allow a responsive wash pumpcontrol. Once the wash spray button has been pressed by the vehicleoperator, the method may set a flag at 1204 indicating that such eventhas occurred. Such flag may be reset once the method completes thewindshield wiping. Similarly, in other embodiments, the method does nothave to remain at 1252 and 1276, respectively and similar periodicchecking as described with respect to 1204 may be applied. In yet otherembodiments, the method may utilize a microprocessor interrupt control,i.e. a switch which is operatively connected to an interrupt input ofthe microprocessor and which signals an interrupt signal to themicroprocessor when the respective switch is closed. Subsequently, aprogram execution for the method may be transferred to a differentportion of the program in response to the respective switch beingclosed.

Yet further, with respect to the embodiment of wiping a windshieldwindow in FIGS. 12a and 12b , one of ordinary skill in the art knows andappreciates that the method does not have to be performed in twoparallel execution paths 1212 through 1256 for the first case and 1260through 1296 for the second case before rejoining again at 1204. In oneor more embodiments, the method may utilize a single path for the firstand second cases and may further utilize flags or variables in thesingle path to trigger actions that differ for the first and secondcases. In addition, the embodiment of wiping a windshield window inFIGS. 12a and 12b has been described with respect to a single wipeperiod, i.e. one up wash and one down wash. One of ordinary skill in theart knows and appreciates that the method of wiping a windshield windowmay utilize other predetermined different wipe periods. For example, inone or more embodiments the predetermined number of wipe periods is two.In yet other embodiments, the predetermined number is more than two wipeperiods.

Further, the embodiment of wiping a windshield window in FIGS. 12a and12b has been described with respect to an up wash and a down wash duringa wiper period. However, as described above, the present disclosure isnot limited by these embodiments. Alternate embodiments may utilize onlyan up wash or only a down wash. Further, other embodiments may utilizemultiple projections of windshield window wiper fluid toward thewindshield window during both, the up wash and the down wash withcorresponding more frequent activation and deactivation of therespective wash pump. Yet other embodiments may activate a wash pump orwash pumps with a predetermined fluid pressure profile to affect thepressure of the wash fluid toward the windshield window. Thepredetermined fluid pressure profile may differ for the up wash and thedown wash. Alternatively, the predetermined fluid pressure profile maydiffer during multiple wash fluid projections during the up wash orduring the down wash. Further, in one or more embodiments, the fluidpressure profile may be different depending on the vehicle speed.

In one more embodiments of the method of wiping a windshield windowdescribed with respect to FIGS. 12a and 12b , the lookup table in 1224and/or 1272 may be substituted. For example, in alternative embodiments,a suitable mathematical expression may be fitted to the calculated orestimated wash pump timing values as a function of input parameters,such as the wiper motor supply voltage, vehicle speed, high/low wipermotor speed, etc. In other embodiments, the lookup table may besubstituted with the determined position of the wiper blade across thewindshield window as a function of time and may be fitted with asuitable mathematical function. Regardless of whether a mathematicalexpression is fitted to the timing values or to the position of thewiper blade as a function of the above referenced input parameters, thewash pump or wash pumps need to be turned on or off at the appropriatetime or wiper position and one can be converted into the other and viceversa.

As described above, when the wiper blade is in the IW position, theinternal wiper blade switch is closed in accordance with one or moreembodiments. In addition, with respect to FIGS. 12a and 12b , a time isreset and started when the wiper blade is in the IW position and thewiper blade switch is closed. Accordingly, the estimation of theposition of the wiper blade during the wiper blade stroke is based onthe wiper blade switch, i.e. a reference signal for the position of thewiper blade from the wiper motor switch. In one or more embodiments, asingle reference signal may be utilized for the up stroke and for thedown stroke of the wiper blade. One of ordinary skill in the art knowsand appreciates that the reference signal may be provided differently.For example, in other embodiments, the estimation of the position of thewiper blade during the wiper blade stroke may be based on measuring apole switching of the wiper motor. The poles of a motor may be in afixed relationship with a known angular rotation of the motor andmeasuring and counting the number of poles switches may be utilized totrack the rotations of the motor and thus the position of the wiperblade on the windshield window.

As described with respect to 1212 through 1220 and 1260 through 1268 inFIG. 12a , one or more embodiments may estimate the position of thewiper blade during the wiper blade stroke based on the speed of thewiper motor, the supply voltage of the wiper motor, and/or on thevehicle speed. However, the present disclosure is not limited to theseembodiments and other embodiments may utilize less or more inputs toestimate the position of the wiper blade on the windshield window duringthe windshield wiping. For example, the vehicle speed input may bereplaced by a measurement of the wiper motor current. That is, at anincreased vehicle speed, the mechanical loading on the wiper arm andwiper blade also increases and therefore the mechanical loading on thewiper motor increases as well. Thus, the wiper motor current measurementmay replace the vehicle speed as inputs to estimate the position of thewiper blade on the windshield window during the windshield wiping.

In addition, in one or more embodiments, the estimation of the positionof the wiper blade during the wiper blade stroke and the synchronizationof the projection of the wash fluid toward the windshield window withthe estimated position of the wiper blade, is performed in a wiper motorassembly, in a wash pump motor assembly, or in a body control module(BCM). However, the present disclosure is not limited to theseembodiments and other embodiments may utilize other locations toestimate the position of the wiper blade on the windshield window duringthe windshield wiping. For example, the placement for the estimation forthe position of the wiper blade may be guided by cost-effectiveness ofthe selected location, i.e. reduced routing of signals, smallercable-tree, easier vehicle integration, proximity to specificcomponents, signals, etc. Further, one or more embodiments may adjustthe pressure of the wash fluid dynamically during the projecting of thewash fluid toward the windshield window, i.e. fluid pressure profile.

In one or more embodiments, the windshield window wiping system includeshardware (e.g., circuitry), software, firmware, or any combinationthereof, that includes functionality to perform at least some functionsdescribed herein in accordance with one or more embodiments of thepresent disclosure. In one or more embodiments, the windshield windowwiping system of the present disclosure is, at least in part, a softwareapplication, or a portion thereof, written in any programming languagethat includes instructions stored on a non-transitory computer readablemedium which, when executed by one or more processors in a computingdevice, enable the computing device to perform the functions describedin accordance with one or more embodiments of the disclosure. Forexample, in one or more embodiments, the non-transitory computerreadable medium may include instructions, which, when executed by aprocessor, cause the processor to perform a wiper blade stroke acrossthe windshield window, to estimate a position of the wiper blade duringthe wiper blade stroke, to project a wash fluid toward the windshieldwindow through a nozzle of the hood mount, and to synchronize theprojection of the wash fluid toward the windshield window with theestimated position of the wiper blade.

In other embodiments, the non-transitory computer readable medium maysynchronize the projection of wash fluid with the estimated position ofthe wiper blade based on a lookup table containing a plurality ofpredetermined timing values, the plurality of predetermined timingvalues is associated with a timing of turning a wash pump on and off,and varies at least in response to one selected from the groupconsisting of a reference signal for a position of the wiper blade, aspeed of the wiper motor, and a supply voltage to the wiper motor. Inyet other embodiments, the synchronization of the projection of washfluid with the estimated position of the wiper blade may be based on amathematical expression. In further embodiments, the synchronization ofthe projection of wash fluid with the estimated position of the wiperblade may be used on yet other techniques.

Embodiments of the present disclosure may be implemented on virtuallyany type of computing system, regardless of the platform being used. Inone or more embodiments, the computing system may be an embeddedmicrocontroller with one or more microprocessors. For example, as shownin FIG. 13, the computing system (1300) may include one or moreprocessor(s) (1304), associated memory (1308) (e.g., random accessmemory (RAM), cache memory, flash memory, etc.), one or more storagedevice(s) (1312) (e.g., a hard disk, an optical drive such as a compactdisk (CD) drive or digital versatile disk (DVD) drive, a flash memorystick, a solid state drive (SSD), etc.), and numerous other elements andfunctionalities. The processor(s) (1304) may be an integrated circuitfor processing instructions. For example, the processor(s) may be one ormore cores, or micro-cores of a processor. The computing system (1300)may also include one or more input device(s) (1320), such as atouchscreen, keyboard, mouse, microphone, touchpad, electronic pen, orany other type of input device.

Further, the computing system (1300) may include one or more outputdevice(s) (1316), such as a screen (e.g., a liquid crystal display(LCD), a plasma display, touchscreen, projector, or other displaydevice), a printer, external storage, or any other output device. One ormore of the output device(s) may be the same or different from the inputdevice(s). The computing system (600) may be connected to a network(1324) (e.g., a local area network (LAN), a wide area network (WAN) suchas the Internet, mobile network, or any other type of network) via anetwork interface connection (not shown). The input and output device(s)may be locally or remotely (e.g., via the network (1324)) connected tothe processor(s) (1304), memory (1308), and storage device(s) (1312).Many different types of embedded and non-embedded computing systemsexist, and the aforementioned input and output device(s) may take otherforms. In one or more embodiments, the computing system may be aheadless system, e.g. no input devices 1320 and/or no output devices1320 are utilized.

In one or more embodiments, the inputs to the computing system includeinputs received from a LIN or a CAN bus. In other embodiments, inputs tothe computing system may be received as interrupt signals or as logichigh/low signal from a switch wired to a microprocessor input. In yetother embodiments, the outputs from the computing system may be directedtoward the LIN or CAN bus. In other embodiments, the outputs from thecomputing system may be directed to an output pin of the microprocessorwhich in turn is connected to a signal driver.

Software instructions in the form of computer readable program code toperform embodiments may be stored, in whole or in part, temporarily orpermanently, on the non-transitory computer readable medium. Suchnon-transitory computer readable medium maybe an erasable programmableread only memory (EPROM), a flash memory, an internal or externalstorage device, a DVD, a CD, or any other computer or embeddedmicrocontroller readable storage medium. Specifically, the softwareinstructions may correspond to computer readable program code orembedded microcontroller readable program code that when executed by aprocessor(s), is configured to perform embodiments of the disclosure. Inaddition, the software instructions and the associated non-transitorycomputer readable medium may also be referred to as firmware. In one ormore embodiments, the firmware of the windshield window wiping systemcan be updated.

While the disclosure has been described with respect to a limited numberof embodiments, those skilled in the art, having benefit of thisdisclosure, will appreciate that other embodiments can be devised whichdo not depart from the scope of the disclosure as disclosed herein.Accordingly, the scope of the disclosure should be limited only by theattached claims.

What is claimed is:
 1. A windshield window wiping system, comprising: awiper blade in contact with a windshield window; a wiper motoroperatively connected to the wiper blade, configured to perform a wiperblade stroke; a reservoir for a wash fluid; a first hood mounted nozzle,configured to project the wash fluid toward the windshield window; awash pump, wherein the wash pump is hydraulically connected to the firsthood mounted nozzle; and a first electronic circuit, configured toestimate a position of the wiper blade during the wiper blade strokebased on an input to the first electronic circuit and to synchronize theprojection of the wash fluid toward the windshield window with theestimated position of the wiper blade.
 2. The windshield window wipingsystem according to claim 1, further comprising: a second hood mountednozzle, wherein the first hood mounted nozzle and the second hoodmounted nozzle are configured to sequentially project the wash fluidtoward the windshield window during an up stroke and a down stroke ofthe wiper blade.
 3. The windshield window wiping system according toclaim 1, wherein the input to the first electronic circuit is areference signal for a position of the wiper blade, provided by a wipermotor switch.
 4. The windshield window wiping system according to claim3, wherein the wiper motor switch is a single limit switch.
 5. Thewindshield window wiping system according to claim 1, wherein the inputto the first electronic circuit is a signal indicative of a poleswitching of the wiper motor.
 6. The windshield window wiping systemaccording to claim 1, wherein the input to the first electronic circuitis at least one selected from the group consisting of a signalindicative of a speed of the wiper motor, a supply voltage of the wipermotor, and a signal indicative of a vehicle speed.
 7. The windshieldwindow wiping system according to claim 1, wherein the first electroniccircuit comprises a microprocessor.
 8. The windshield window wipingsystem according to claim 1, wherein the first electronic circuit islocated in at least one selected from the group consisting of a wipermotor assembly, a wash pump motor assembly, and in a body control module(BCM).
 9. The windshield window wiping system according to claim 1,wherein the wash pump comprises a wash pump motor which is controlled bya second electronic circuit, the second electronic circuit is configuredto dynamically adjust a pressure of the wash fluid by pulse-widthmodulation (PWM) of the wash pump motor during the wiper blade stroke.10. The windshield window wiping system according to claim 9, wherein aprofile of the dynamically adjusted pressure is dependent on a vehiclespeed.
 11. The windshield window wiping system according to claim 1,further comprising: a restriction valve for the wash fluid, wherein thefirst hood mounted nozzle is configured to project the wash fluid towardthe windshield window at a lower pressure during an up stroke and at ahigher pressure during a down stroke, wherein the lower pressure of thewash fluid during the up stroke projects the wash fluid at a lowerposition onto the windshield than the projected position of the washfluid on the windshield at higher pressure, and wherein the restrictionvalve restricts a flow of the wash fluid during the projection of washfluid toward the windshield window at lower pressure.
 12. A method ofwiping a windshield window, comprising: operatively connecting a wipermotor to a wiper blade; bringing the wiper blade in contact with awindshield window; estimating a position of the wiper blade during awiper blade stroke across the windshield window; projecting a wash fluidtoward the windshield window through a first hood mounted nozzle; andsynchronizing the projection of wash fluid toward the windshield windowwith the estimated position of the wiper blade.
 13. The method of wipinga windshield window according to claim 12, further comprising:projecting a wash fluid toward the windshield window through a secondhood mounted nozzle, wherein the first hood mounted nozzle and thesecond hood mounted nozzle are configured to sequentially project thewash fluid toward the windshield window during an up stroke and a downstroke of the wiper blade.
 14. The method of wiping a windshield windowaccording to claim 12, wherein the estimating of the position of thewiper blade during the wiper blade stroke is based on a reference signalfor a position of the wiper blade from a wiper motor switch.
 15. Themethod of wiping a windshield window according to claim 14, wherein thereference signal is a single reference signal for an up stroke and adown stroke of the wiper blade.
 16. The method of wiping a windshieldwindow according to claim 12, wherein the estimating of the position ofthe wiper blade during the wiper blade stroke is based on a poleswitching of the wiper motor.
 17. The method of wiping a windshieldwindow according to claim 12, wherein the estimating of the position ofthe wiper blade during the wiper blade stroke is based on at least oneselected from the group consisting of a signal indicative of a speed ofthe wiper motor, a supply voltage of the wiper motor, and a signalindicative of a vehicle speed.
 18. The method of wiping a windshieldwindow according to claim 12, wherein the estimating of the position ofthe wiper blade during the wiper blade stroke and the synchronizing ofthe projection of the wash fluid toward the windshield window with theestimated position of the wiper blade is done in at least one selectedfrom the group consisting of a wiper motor assembly, a wash pump motorassembly, and a body control module (BCM).
 19. The method of wiping awindshield window according to claim 12, wherein during the projectingof the wash fluid toward the windshield window, the pressure of the washfluid is dynamically adjusted.
 20. The method of wiping a windshieldwindow according to claim 19, wherein during the dynamically adjustingof the wash fluid, a profile of the pressure is dependent on a vehiclespeed.
 21. The method of wiping a windshield window according to claim12, further comprising: projecting a wash fluid toward the windshieldwindow from the first hood mounted nozzle at a lower pressure during anup stroke and at a higher pressure during a down stroke and restrictinga flow of the wash fluid during the projection of wash fluid toward thewindshield window at lower pressure, wherein the lower pressure of thewash fluid during the up stroke projects the wash fluid at a lowerposition onto the windshield than the projected position of the washfluid on the windshield at higher pressure.
 22. A non-transitorycomputer readable medium comprising instructions, which, when executedby a processor, cause the processor to: perform a wiper blade strokeacross the windshield window; estimate a position of the wiper bladeduring the wiper blade stroke; project a wash fluid toward thewindshield window through a hood mounted nozzle; and synchronize theprojection of the wash fluid toward the windshield window with theestimated position of the wiper blade.
 23. The non-transitory computerreadable medium according to claim 22, wherein the projection of washfluid is synchronized with the estimated position of the wiper bladebased on a lookup table containing a plurality of predetermined timingvalues, the plurality of predetermined timing values is associated witha timing of turning a wash pump on and off, and varies at least inresponse to one selected from the group consisting of a reference signalfor a position of the wiper blade, a speed of the wiper motor, and asupply voltage to the wiper motor.